/* * Copyright 2007-2010 Red Hat, Inc. * by Peter Jones * Copyright 2007 IBM, Inc. * by Konrad Rzeszutek * Copyright 2008 * by Konrad Rzeszutek * * This code finds the iSCSI Boot Format Table. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License v2.0 as published by * the Free Software Foundation * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Physical location of iSCSI Boot Format Table. */ struct acpi_table_ibft *ibft_addr; EXPORT_SYMBOL_GPL(ibft_addr); static const struct { char *sign; } ibft_signs[] = { #ifdef CONFIG_ACPI /* * One spec says "IBFT", the other says "iBFT". We have to check * for both. */ { ACPI_SIG_IBFT }, #endif { "iBFT" }, { "BIFT" }, /* Broadcom iSCSI Offload */ }; #define IBFT_SIGN_LEN 4 #define IBFT_START 0x80000 /* 512kB */ #define IBFT_END 0x100000 /* 1MB */ #define VGA_MEM 0xA0000 /* VGA buffer */ #define VGA_SIZE 0x20000 /* 128kB */ #ifdef CONFIG_ACPI static int __init acpi_find_ibft(struct acpi_table_header *header) { ibft_addr = (struct acpi_table_ibft *)header; return 0; } #endif /* CONFIG_ACPI */ static int __init find_ibft_in_mem(void) { unsigned long pos; unsigned int len = 0; void *virt; int i; for (pos = IBFT_START; pos < IBFT_END; pos += 16) { /* The table can't be inside the VGA BIOS reserved space, * so skip that area */ if (pos == VGA_MEM) pos += VGA_SIZE; virt = isa_bus_to_virt(pos); for (i = 0; i < ARRAY_SIZE(ibft_signs); i++) { if (memcmp(virt, ibft_signs[i].sign, IBFT_SIGN_LEN) == 0) { unsigned long *addr = (unsigned long *)isa_bus_to_virt(pos + 4); len = *addr; /* if the length of the table extends past 1M, * the table cannot be valid. */ if (pos + len <= (IBFT_END-1)) { ibft_addr = (struct acpi_table_ibft *)virt; goto done; } } } } done: return len; } /* * Routine used to find the iSCSI Boot Format Table. The logical * kernel address is set in the ibft_addr global variable. */ unsigned long __init find_ibft_region(unsigned long *sizep) { #ifdef CONFIG_ACPI int i; #endif ibft_addr = NULL; #ifdef CONFIG_ACPI for (i = 0; i < ARRAY_SIZE(ibft_signs) && !ibft_addr; i++) acpi_table_parse(ibft_signs[i].sign, acpi_find_ibft); #endif /* CONFIG_ACPI */ /* iBFT 1.03 section 1.4.3.1 mandates that UEFI machines will * only use ACPI for this */ if (!ibft_addr && !efi_enabled) find_ibft_in_mem(); if (ibft_addr) { *sizep = PAGE_ALIGN(ibft_addr->header.length); return (u64)isa_virt_to_bus(ibft_addr); } *sizep = 0; return 0; }